Hepatitis A, B, and C.

During the past 30 years, the understanding of hepatitis viruses has greatly expanded. Knowledge of hepatitis has progressed from merely describing the various clinical syndromes to a greater understanding of the pathogenesis of disease caused by these viruses and the development of chronic infection that eventually leads to cirrhosis or hepatocellular carcinoma. Expanded understanding also has led to the development of effective vaccines against hepatitis A virus (HAV) and hepatitis B virus (HBV) and antiviral therapies against hepatitis Cvirus (HCV). The introduction of routine vaccination against HAV and HBV starting in early childhood in the United States has resulted in a substantial decrease in both of these infections in children and the subsequent complications of HBVrelated chronic liver disease. Effective screening of mothers during pregnancy and the administration of HBV vaccine soon after birth, along with administration of hepatitis B immune globulin (HBIG) to infants born to women who have HBV infection, has led to near eradication of perinatally acquired HBVdisease in the United States and other countries with effective screening programs. The introduction and routine administration of HAV vaccine in the United States in the 1990s led to near complete elimination of HAV outbreaks among children. AUTHOR DISCLOSURE Drs Christenson and Manaloor have disclosed no financial relationships relevant to this article. This commentary does contain a discussion of an unapproved/investigative use of a commercial product/device.